Aim: The aim of this review was to assess the relationship between delivery by elective caesarean section and respiratory morbidity in the term and near-term neonate.
Methods: Searches were made in the MEDLINE database, EMBASE, Cochrane database and Web of Science to identify peer-reviewed studies in English on elective caesarean section and respiratory morbidity in the newborn. We included studies that compared elective caesarean section to vaginal or intended vaginal delivery, with clear definition of outcome measures and information about gestational age.
Results: Nine eligible studies were identified. All studies found that delivery by elective caesarean section increased the risk of various respiratory morbidities in the newborn near term compared with vaginal delivery, although the findings were not statistically significant in all studies. It was inappropriate to carry out a meta-analysis with a pooled risk estimate because of a variety of methodological differences between the studies. The overall risk for respiratory morbidity, however, seemed to increase about 2 to 3 times, though some studies presented much higher risk estimates. A decreasing risk with increasing gestational age was shown in 2 studies.
Conclusion: Delivery by elective caesarean section was shown to increase the risk of respiratory morbidity in all studies eligible for inclusion. The magnitude of this relative risk seemed to depend on gestational age even in deliveries after 37 completed weeks of gestation.